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diff --git a/policy-management/src/main/java/org/onap/policy/drools/system/internal/SimpleLockManager.java b/policy-management/src/main/java/org/onap/policy/drools/system/internal/SimpleLockManager.java
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+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.drools.system.internal;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Properties;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicReference;
+import lombok.AccessLevel;
+import lombok.Getter;
+import lombok.Setter;
+import org.onap.policy.common.utils.properties.exception.PropertyException;
+import org.onap.policy.common.utils.time.CurrentTime;
+import org.onap.policy.drools.core.lock.AlwaysFailLock;
+import org.onap.policy.drools.core.lock.Lock;
+import org.onap.policy.drools.core.lock.LockCallback;
+import org.onap.policy.drools.core.lock.LockImpl;
+import org.onap.policy.drools.core.lock.LockState;
+import org.onap.policy.drools.core.lock.PolicyResourceLockManager;
+import org.onap.policy.drools.system.PolicyEngine;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+
+/**
+ * Simple implementation of the Lock Feature. Locks do not span across instances of this
+ * object (i.e., locks do not span across servers).
+ *
+ * <p/>
+ * Note: this implementation does <i>not</i> honor the waitForLocks={@code true}
+ * parameter.
+ *
+ * <p/>
+ * When a lock is deserialized, it will not initially appear in this feature's map; it
+ * will be added to the map once free() or extend() is invoked, provided there isn't
+ * already an entry.
+ */
+public class SimpleLockManager implements PolicyResourceLockManager {
+
+    private static final Logger logger = LoggerFactory.getLogger(SimpleLockManager.class);
+
+    private static final String NOT_LOCKED_MSG = "not locked";
+    private static final String LOCK_LOST_MSG = "lock lost";
+
+    /**
+     * Provider of current time. May be overridden by junit tests.
+     */
+    private static CurrentTime currentTime = new CurrentTime();
+
+    @Getter(AccessLevel.PROTECTED)
+    @Setter(AccessLevel.PROTECTED)
+    private static SimpleLockManager latestInstance = null;
+
+
+    /**
+     * Engine with which this manager is associated.
+     */
+    private final PolicyEngine engine;
+
+    /**
+     * Feature properties.
+     */
+    private final SimpleLockProperties featProps;
+
+    /**
+     * Maps a resource to the lock that owns it.
+     */
+    private final Map<String, SimpleLock> resource2lock = new ConcurrentHashMap<>();
+
+    /**
+     * Thread pool used to check for lock expiration and to notify owners when locks are
+     * lost.
+     */
+    private ScheduledExecutorService exsvc = null;
+
+    /**
+     * Used to cancel the expiration checker on shutdown.
+     */
+    private ScheduledFuture<?> checker = null;
+
+
+    /**
+     * Constructs the object.
+     *
+     * @param engine engine with which this manager is associated
+     * @param properties properties used to configure the manager
+     */
+    public SimpleLockManager(PolicyEngine engine, Properties properties) {
+        try {
+            this.engine = engine;
+            this.featProps = new SimpleLockProperties(properties);
+
+        } catch (PropertyException e) {
+            throw new SimpleLockManagerException(e);
+        }
+    }
+
+    @Override
+    public boolean isAlive() {
+        return (checker != null);
+    }
+
+    @Override
+    public boolean start() {
+        if (checker != null) {
+            return false;
+        }
+
+        exsvc = getThreadPool();
+
+        checker = exsvc.scheduleWithFixedDelay(this::checkExpired, featProps.getExpireCheckSec(),
+                        featProps.getExpireCheckSec(), TimeUnit.SECONDS);
+
+        setLatestInstance(this);
+
+        return true;
+    }
+
+    /**
+     * Stops the expiration checker. Does <i>not</i> invoke any lock call-backs.
+     */
+    @Override
+    public synchronized boolean stop() {
+        exsvc = null;
+
+        if (checker == null) {
+            return false;
+        }
+
+        ScheduledFuture<?> checker2 = checker;
+        checker = null;
+
+        checker2.cancel(true);
+
+        return true;
+    }
+
+    @Override
+    public void shutdown() {
+        stop();
+    }
+
+    @Override
+    public boolean isLocked() {
+        return false;
+    }
+
+    @Override
+    public boolean lock() {
+        return true;
+    }
+
+    @Override
+    public boolean unlock() {
+        return true;
+    }
+
+    @Override
+    public Lock createLock(String resourceId, String ownerKey, int holdSec, LockCallback callback,
+                    boolean waitForLock) {
+
+        if (latestInstance != this) {
+            AlwaysFailLock lock = new AlwaysFailLock(resourceId, ownerKey, holdSec, callback);
+            lock.notifyUnavailable();
+            return lock;
+        }
+
+        SimpleLock lock = makeLock(LockState.WAITING, resourceId, ownerKey, holdSec, callback);
+
+        SimpleLock existingLock = resource2lock.putIfAbsent(resourceId, lock);
+
+        if (existingLock == null) {
+            lock.grant();
+        } else {
+            lock.deny("resource is busy");
+        }
+
+        return lock;
+    }
+
+    /**
+     * Checks for expired locks.
+     */
+    private void checkExpired() {
+        long currentMs = currentTime.getMillis();
+        logger.info("checking for expired locks at {}", currentMs);
+
+        /*
+         * Could do this via an iterator, but using compute() guarantees that the lock
+         * doesn't get extended while it's being removed from the map.
+         */
+        for (Entry<String, SimpleLock> ent : resource2lock.entrySet()) {
+            if (!ent.getValue().expired(currentMs)) {
+                continue;
+            }
+
+            AtomicReference<SimpleLock> lockref = new AtomicReference<>(null);
+
+            resource2lock.computeIfPresent(ent.getKey(), (resourceId, lock) -> {
+                if (lock.expired(currentMs)) {
+                    lockref.set(lock);
+                    return null;
+                }
+
+                return lock;
+            });
+
+            SimpleLock lock = lockref.get();
+            if (lock != null) {
+                lock.deny("lock expired");
+            }
+        }
+    }
+
+    /**
+     * Simple Lock implementation.
+     */
+    public static class SimpleLock extends LockImpl {
+        private static final long serialVersionUID = 1L;
+
+        /**
+         * Time, in milliseconds, when the lock expires.
+         */
+        @Getter
+        private long holdUntilMs;
+
+        /**
+         * Feature containing this lock. May be {@code null} until the feature is
+         * identified. Note: this can only be null if the lock has been de-serialized.
+         */
+        private transient SimpleLockManager feature;
+
+        /**
+         * Constructs the object.
+         */
+        public SimpleLock() {
+            this.holdUntilMs = 0;
+            this.feature = null;
+        }
+
+        /**
+         * Constructs the object.
+         *
+         * @param state initial state of the lock
+         * @param resourceId identifier of the resource to be locked
+         * @param ownerKey information identifying the owner requesting the lock
+         * @param holdSec amount of time, in seconds, for which the lock should be held,
+         *        after which it will automatically be released
+         * @param callback callback to be invoked once the lock is granted, or
+         *        subsequently lost; must not be {@code null}
+         * @param feature feature containing this lock
+         */
+        public SimpleLock(LockState state, String resourceId, String ownerKey, int holdSec, LockCallback callback,
+                        SimpleLockManager feature) {
+            super(state, resourceId, ownerKey, holdSec, callback);
+            this.feature = feature;
+        }
+
+        /**
+         * Determines if the owner's lock has expired.
+         *
+         * @param currentMs current time, in milliseconds
+         * @return {@code true} if the owner's lock has expired, {@code false} otherwise
+         */
+        public boolean expired(long currentMs) {
+            return (holdUntilMs <= currentMs);
+        }
+
+        /**
+         * Grants this lock. The notification is <i>always</i> invoked via a background
+         * thread.
+         */
+        protected synchronized void grant() {
+            if (isUnavailable()) {
+                return;
+            }
+
+            setState(LockState.ACTIVE);
+            holdUntilMs = currentTime.getMillis() + TimeUnit.SECONDS.toMillis(getHoldSec());
+
+            logger.info("lock granted: {}", this);
+
+            feature.exsvc.execute(this::notifyAvailable);
+        }
+
+        /**
+         * Permanently denies this lock. The notification is invoked via a background
+         * thread, if a feature instance is attached, otherwise it uses the foreground
+         * thread.
+         *
+         * @param reason the reason the lock was denied
+         */
+        protected void deny(String reason) {
+            synchronized (this) {
+                setState(LockState.UNAVAILABLE);
+            }
+
+            logger.info("{}: {}", reason, this);
+
+            if (feature == null) {
+                notifyUnavailable();
+
+            } else {
+                feature.exsvc.execute(this::notifyUnavailable);
+            }
+        }
+
+        @Override
+        public boolean free() {
+            // do a quick check of the state
+            if (isUnavailable()) {
+                return false;
+            }
+
+            logger.info("releasing lock: {}", this);
+
+            if (!attachFeature()) {
+                setState(LockState.UNAVAILABLE);
+                return false;
+            }
+
+            AtomicBoolean result = new AtomicBoolean(false);
+
+            feature.resource2lock.computeIfPresent(getResourceId(), (resourceId, curlock) -> {
+
+                if (curlock == this) {
+                    // this lock was the owner - resource is now available
+                    result.set(true);
+                    setState(LockState.UNAVAILABLE);
+                    return null;
+
+                } else {
+                    return curlock;
+                }
+            });
+
+            return result.get();
+        }
+
+        @Override
+        public void extend(int holdSec, LockCallback callback) {
+            if (holdSec < 0) {
+                throw new IllegalArgumentException("holdSec is negative");
+            }
+
+            setHoldSec(holdSec);
+            setCallback(callback);
+
+            // do a quick check of the state
+            if (isUnavailable() || !attachFeature()) {
+                deny(LOCK_LOST_MSG);
+                return;
+            }
+
+            if (feature.resource2lock.get(getResourceId()) == this) {
+                grant();
+            } else {
+                deny(NOT_LOCKED_MSG);
+            }
+        }
+
+        /**
+         * Attaches to the feature instance, if not already attached.
+         *
+         * @return {@code true} if the lock is now attached to a feature, {@code false}
+         *         otherwise
+         */
+        private synchronized boolean attachFeature() {
+            if (feature != null) {
+                // already attached
+                return true;
+            }
+
+            feature = latestInstance;
+            if (feature == null) {
+                logger.warn("no feature yet for {}", this);
+                return false;
+            }
+
+            // put this lock into the map
+            feature.resource2lock.putIfAbsent(getResourceId(), this);
+
+            return true;
+        }
+
+        @Override
+        public String toString() {
+            return "SimpleLock [state=" + getState() + ", resourceId=" + getResourceId() + ", ownerKey=" + getOwnerKey()
+                            + ", holdSec=" + getHoldSec() + ", holdUntilMs=" + holdUntilMs + "]";
+        }
+    }
+
+    // these may be overridden by junit tests
+
+    protected ScheduledExecutorService getThreadPool() {
+        return engine.getExecutorService();
+    }
+
+    protected SimpleLock makeLock(LockState waiting, String resourceId, String ownerKey, int holdSec,
+                    LockCallback callback) {
+        return new SimpleLock(waiting, resourceId, ownerKey, holdSec, callback, this);
+    }
+}